28877557 has 2 divisors, whose sum is σ = 28877558. Its totient is φ = 28877556.

The previous prime is 28877531. The next prime is 28877561. The reversal of 28877557 is 75577882.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27783441 + 1094116 = 5271^2 + 1046^2 .

It is a cyclic number.

It is not a de Polignac number, because 28877557 - 2¹⁵ = 28844789 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28877557.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28877507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14438778 + 14438779.

It is an arithmetic number, because the mean of its divisors is an integer number (14438779).

Almost surely, 2^28877557 is an apocalyptic number.

It is an amenable number.

28877557 is a deficient number, since it is larger than the sum of its proper divisors (1).

28877557 is an equidigital number, since it uses as much as digits as its factorization.

28877557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1097600, while the sum is 49.

The square root of 28877557 is about 5373.7842345967. The cubic root of 28877557 is about 306.7986775434.

The spelling of 28877557 in words is "twenty-eight million, eight hundred seventy-seven thousand, five hundred fifty-seven".